Cuba is also home to the oldest overseas U.S. Navy base, Guantanamo Bay. Today, it serves as the site of the Guantanamo Bay Detention Camp for combatants captured in Afghanistan and Iraq. When President Barack Obama came into office, he promised to close the military prison for good, but since then, lawmakers have barred the transfer of Guantanamo detainees to the continental United States and they've required that prisoners there face military trials. NPR's Dina Temple-Raston was at Guantanamo recently. She reports that the prison is beginning to feel permanent.

DINA TEMPLE-RASTON, BYLINE: I've reported on prisons for years, but Guantanamo felt different. In regular prisons, I've had some sort of contact with the inmates, but in Guantanamo, the prisoners are behind glass. It's like a terrorist museum.

UNIDENTIFIED MAN #1: Welcome to camp six. This is the compliant camp within this mission.

TEMPLE-RASTON: That's the officer in charge of camp six. This is where nearly all of the 171 detainees live. I'm watching their lives from behind dark one-way glass, and they don't know I'm there. It's like a silent movie: you see the actors but you can't hear them.

UNIDENTIFIED MAN #1: As we walk around, once we come out here, we're going to make a left and we're going to...

TEMPLE-RASTON: So, you end up adding a mental soundtrack as bearded men in prison garb climb stairs, do laundry, move in and out of interior cells. They can watch TV on 46-inch flat screens on the wall or play Nintendo or go to class.

TEMPLE-RASTON: Camp five was built in the U.S., disassembled like a Lego project and then floated on a barge to Cuba.

UNIDENTIFIED MAN #2: All right. We'll go ahead and take you inside.

TEMPLE-RASTON: An Army officer walks us in. On any given day, there are only about 20 or 30 detainees here.

UNIDENTIFIED MAN #2: So, if detainees in camp six break one of the camp rules, to include assaulting the guard force with urine and feces, they're brought over here to camp five to serve out their discipline time.

TEMPLE-RASTON: You can get 20 days in camp five for that. I look up at the white ceiling. I can still see brown splatters from past attempts. A typical cell is a little more than eight feet by ten feet. There's no furniture - just the essentials.

UNIDENTIFIED MAN #2: This is a toilet, sink, water fountain combination; very common to what you'll see in any facility in the United States. It's built to be indestructible. Detainees, they really can't damage or alter this in any way.

TEMPLE-RASTON: Detainees who follow orders have a two-inch mattress and up to eight books from the detainee library. Misbehave, the mattress gets thinner, they get fewer books. We asked about the detainees, whether there had been hunger strikes. And one of the press handlers jumped in. Apparently, we'd asked one too many questions.

UNIDENTIFIED MAN #2: Are we out of time?

UNIDENTIFIED WOMAN: Yeah, out of time.

UNIDENTIFIED MAN #2: OK. All right. All right. Hey, ladies and gentlemen, it's been a pleasure. All right. Come back any time.

TEMPLE-RASTON: Which is possible. The prison at Guantanamo isn't closing any time soon.